摘要
针对埋刮板垂直输送过程中物料滞后问题,首先通过埋刮板垂直输送过程中物料的结拱条件理论分析,建立物料垂直整体输送的理论模型,明确影响物料结拱的因素有刮板内圈周长、刮板间距、物料间内摩擦系数等参数;其次,在离散元仿真中创建垂直埋刮板输送机几何模型,并采用HERTZ-MINDLIN无滑动接触模型,设置刮板、物料的运动参数、材料参数、材料接触参数模拟埋刮板垂直输送过程中物料颗粒的位置分布与速度分布,验证物料滞后现象;最后,通过EDEM仿真揭示了刮板内圈周长、刮板间距、物料间摩擦系数、给料速率、链条速度等参数对埋刮板垂直输送过程中物料的滞后程度的影响规律。结果表明:增大物料内摩擦系数,减小刮板内圈周长和刮板间距等可以减小物料结拱所需的垂直内压力,从而减小物料垂直输送的滞后程度。物料内摩擦系数分别取0.2,0.25,0.3,0.35,0.4时,物料的滞后程度分别为27%,24%,19%,17%,15%;刮板的内圈周长分别取436,476,516,556,596mm时,物料的滞后程度分别为14%,17%,21%,23%,27%;刮板间距分别取100,120,140,160,180mm时,物料的滞后程度分别为24%,27%,30%,33%,35%。刮板链条速度的增大对于物料颗粒的垂直输送速度的提升并无明显的作用,反而会加剧物料垂直运输的滞后程度,而增大物料的给料速率对于物料的垂直输送速度有着显著的提升,可以较大减轻物料垂直输送的滞后程度。本研究成果可为提升垂直埋刮板输送性能提供参考。
Aiming at the problem of material lag in vertical buried scraper conveying process, the vertical buried scraper conveying theoretical model of material was firstly established through theoretical analysis of material arching condition, and the influences of inner circle of scraper, spacing of scraper, coefficient of internal friction between materials, etc. were clarified.Furthermore, the geometric model of vertical buried scraper conveyor was established in DEM simulation, the Hertz-Mindlin nonsliding contact model was adopted. Then the movement parameters, material parameters and material contact parameters of scraper were set to simulate the distribution of particles position and particles velocity in vertical conveying process, and the lag phenomenon of particle was verified. Finally, the influences of parameters such as inner circle circumference of scraper, scraper spacing, and friction coefficient between materials, feeding rate and chain speed on the lagging degree of particle were revealed.These results showed that the vertical internal pressure required for material arching can be reduced by increasing the particle internal friction coefficient and reducing the inner circumference of scraper,thereby alleviating the particle lagging phenomenon.Particle internal friction was 0.2,0.25,0.3,0.35,0.4,particle lagging degree was 27%,24%,19%,17%,15%,respectively;Particle internal friction was 0.2,0.25,0.3,0.35,0.4,particle lagging degree was 27%,24%,19%,17%,15%,respectively;inner circumference of scraper was 436,476,516,556,596 mm, particle lagging degree was 14%,17%,21%,23%,27%,respectively;spacing of scraper was 100,120,140,160,180 mm, particle lagging degree was 24%,27%,30%,33%,35%,respectively;the increase of scraper chain speed had no obviously effected on the increase of the particle vertical conveying speed, but the particle lagging phenomenon was aggravated;increasing the feed rate of material had a significant increase on the vertical transport speed of material, which led the particle lagging degree greatly reduce. This research provides a reference for improving the vertical buried scraper conveying performance.
作者
袁建明
刘斯齐
叶方平
胡志辉
YUAN Jian-ming;LIU Si-qi;YE Fang-ping;HU Zhi-hui(School of Logistics Engineering,Wuhan University of Technology,Wuhan 430063,China;School of Mechanical Engineering,Hubei University of Technology,Wuhan 430068,China)
出处
《沈阳农业大学学报》
CAS
CSCD
北大核心
2020年第2期212-217,共6页
Journal of Shenyang Agricultural University
基金
国家自然科学基金项目(51275369)
国家科技支撑计划项目(2015BAF06B05)。
关键词
埋刮板
垂直输送
散料起拱
物料滞后
离散元仿真
buried scraper
vertical conveying
bulk material arching
material lag
DEM simulation
